1. Technical Field
This invention relates to photography and photographic sheet film and, in particular, to the holding, feeding, retrieving and storing of photographic film in a sheet format as it is used in a large format camera.
The term, large format, relates to cameras that use large-size sheet film, 4".times.5" and larger. It is well known in the art that the large format camera offers maximum versatility and many other special features that allow greater flexibility in creative control and, in addition the large-size film produces better quality, less graininess and a much greater range of tonal values. However, another characteristic of the large format camera and not a desireable one is that a single sheet of film, one at a time, must be inserted into the camera for each exposure and then the sheet of film must be removed before the next sheet of film can be inserted. Further, during this time-consuming process, the sheet of film must be protected from light.
2. Prior Art
Known photographic sheet film-handling devices for the large format camera are individual film holders that require not only tedious preparation, loading and unloading of individual sheets of film both before and after use, but an additional time-consuming procedure is necessary in bringing each sheet of film to and from an exposure position or focal plane even after the sheet is inserted into the camera.
There are a number of these types of film-holding devices on the market with slight variations. One representative device is Film Holder, U.S. Pat. No. 2,496,271. This device holds two sheets of film, and prior to insertion in the camera, these two sheets must be individually placed in the film holder in a light-tight environment.
The loading procedure is as follows: In a light-tight environment, the first sheet of film is placed in the film holder and then covered with a light-blocking slide. The holder is then turned over, the second sheet is placed on the opposite side, and the second sheet is covered with a light-blocking slide. If the photographer plans to shoot more than two sheets of film. he must fill additional film holders in this same manner or, after exposing those two sheets, return to the light-tight environment to re-fill the original holder.
The picture-taking procedure is as follows: Once the two sheets are placed in the holder, the film holder must then be inserted into the focal plane of the camera, the light-blocking slide removed from the camera, and the sheet of film exposed. After exposure, the light-blocking slide is replaced and the film holder is removed from the camera. The holder is then turned over, after which it is again inserted into the focal plane and the second sheet is exposed and the process is repeated.
To use a third sheet or more, as previously stated, additional film holders would have to be prepared in advance or the photographer would have to return to the light-tight environment and un-load and re-fill the original film holder.
Heretofore, this tedious and time-consuming method of loading and unloading individual sheets of film has long plagued the large format camera user. Therefore, fashion photographers and others needing the ability to shoot a large amount of film in a short period of time have had to turn to the smaller format camera to get the speed and quantity they needed.
While the time and tediousness of the single sheet loading method is reason enough for an improvement in the state of the art, the convenience of having multiple sheets of film available at hand and the ability to shoot another sheet of film immediately is wanted and needed by the large format camera photographer.